#include <REGX52.H>

void Delay(unsigned int xms)		//@12.000MHz
{
	unsigned char i, j;

	while(xms) {
		i = 2;
		j = 239;

		do{
			while (--j);
		} while (--i);
		--xms;
	}

}


void main(){
	
	while(1){
		if(P3_1==0){
			Delay(20);	
			while(P3_1 != 1);
			Delay(20);
			P2_7 = ~P2_7;
		}
	}
}